/*
 * Proja - project management software
 * Copyright (C) 2012  Oleg Kasian
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 */
package org.proja.core.util;

import java.util.Map.Entry;

/**
 * Interface to provide access to session,
 * from core library.
 * @author Oleg Kasian
 * @version 1.0.0
 */
public interface SessionDataStorage extends Iterable<Entry<String, Object>> {

    /**
     * Adds new object to session.
     * @param key object key
     * @param value object value
     */
    void add(String key, Object value);

    /**
     * Return object from session.
     * @param key object key
     * @return object for the given key or null
     */
    Object get(String key);

    /**
     * Removes object from session, if one exists.
     * @param key object key
     * @throws IllegalArgumentException if no object for the given
     * key is found
     */
    void remove(String key) throws IllegalArgumentException;

    /**
     * Checks if the object is found in session.
     * @param key object key
     * @return true if object is found
     */
    boolean contains(String key);
}
